Disclaimer: I don't own Naruto and its quiet pointless to argue that fact.
As Tsunade took a sip from her sake bottle, she reflected that it had been three years since Orochimaru slaughtered their former teacher, the third Hokage. Three years since she had become the fifth Hokage of the village hidden in the leaves. Three years since she picked the replacements of the legendary Sannin of Konaha.
When she first meet team 7 it was like looking back at herself Jiraiya and Orochimaru in their Genin days. Yet there was something. Something that they had that she and her team never had. A seemingly unbreakable bond between the three of them that she and her former teammates never had. It was as she watched Naruto proclaim that he would defeat Sasuke and the raven head merely smirked, that she decided that they would become the sannin that she and her teammates could never be. Jiraiya had already taken Naruto as his subordinate, but never had the motivation to seriously train. Sakura lacked the will and confidence to reach her potential. Sasuke lacked a teacher that could bring out potential. Kakashi as good as a teacher as he was could never full be able to bring the Uchiha's full potential.
So when she found out that the snake sannin had taken an interest in one of the last two remaining Uchiha's that she put her plan into full gear. Setting the motions that would lead to Uchiha's betrayal and a teacher that would be able to give him what he needed as well as giving the other two the drive necessary to become their replacements.
Many would think her unable to pull of such a task. After she was a loud mouth gambling, alcoholic who seemingly lazing around avoiding doing any work. Years of being on the same squad along with Orochimaru had made her a brilliant tactician and manipulator
Manipulating Sasuke had been relatively easy. All she had to do was constantly dropped hints around him, telling of Orochimaru genius, abilities and knowledge of various jutsu's. Nothing too suspicious, just various drops and there in there conversations. So when a couple of weeks later Sasuke betrayed the village and She had to pretend to be in shock while secretly grinning all the while.
She had sent Naruto along with a batch of genins lead by Shikamaru to chase after the 'kidnapped' Sasuke. She knew she had set them up for failure, she could have easily sent a couple of Jounin to retrieve him, but that would defeat her whole purpose. So when Naruto returned defeated and empty handed, swearing he would grow strong enough to save Sasuke and Sakura came to her the next day begging to be trained, she had to hid the tiny smirk that had grown on her face.
Naruto had returned the day before. Now that he was back the final steps in her plan were ready to start,
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Yeah I find this piece a bit odd as well. Its just that I feel that there's more to the Tsunade character then most people think. I believe that she's far more intelligent and more manipulative them she appears. I mean come on she was on the same squad as Orochimaru for how many years, some of his ways had to rub off on her and Jiraiya as well as vice versa.